The present invention relates to a system for providing some service to a user, such as a home use robot, an information terminal, or the like, and particularly relates to a technology for enabling provision of further appropriate service to user's state.
Recently, appliances are demanded which are capable of providing complicated information or service to a user, such as home use robots, information terminals, and the like and the reduction to practical use thereof are being promoted. Information and service which can be provided through such appliances expand over a wide range and a function capable of performing operation according to user's preference is demanded. Under the circumstances, how suitable operation for user's state can be performed is one of important factors for determining appliance's performance.
Various techniques have been proposed as conventional techniques for detecting user's state. For example, it can be said that input tools such as buttons, key boards, mouses are means for notifying user's request or the like to an appliance. Further, if user's mental state or intention could be detected in addition to the user's request, the appliance could exhibit further advanced adaptability. Particularly, it is desirable to detect a state in which a user feels some discontent. For example, when a user would feel that an appliance does not operate as the user desires, some improved counter-response could be offered if the appliance could detect the user's discontent but the response could not be changed without detection thereof.
Referring to detection of user's discontent, Patent Document 1 discloses a technique that: a user might express discontent through an action of banging an appliance when the appliance performs operation that the user does not desire, and the action of banging or vibration of the appliance is detected to change information that the appliance is providing.
Further, a method of detecting user's state through a biological signal may be considered. For example, Patent Document 2 discloses that measurement and processing of a physiological reaction in electrocardiogram, electroencephalogram, sphygmogram, or the like can attain judgment of an awaking level, an attention level, sleepiness, tiredness, mental burden, physical comfort, or the like.
On the other hand, in cognitive psychology and clinical medical science, study using physiological indexes such as an electroencephalogram (EEG) has progressed. According to Non-patent Document 1, for example, diagnoses of dementia, melancholia, schizophrenia, higher order cognition disorder, and the like and effect judgments of various medicine and rehabilitation are carried out using electroencephalographs.
(Patent Document 1) Japanese Patent Application Laid Open Publication No. 2002-281186A
(Patent Document 2) Japanese Patent Application Laid Open Publication No. 5-15599A
(Non-patent Document 1) “Manual of Event-Related Potentials (ERP)—Centering on P300-,” by Kaga et al., published by Shinohara Shuppan Shinsha, 1995
(Non-patent Document 2) “Neo Physiological Psychology,” by Fujisawa et al., published by Kitaohji Shobo, 1998